Republican presidential candidate Donald Trump participates in a roundtable discussion on national security in his offices in Trump Tower in New York on Wednesday.

Donald Trump’s latest campaign shakeup is clinching proof that he has learned nothing from his disastrous summer — let alone from the wider arc of his 14-month presidential quest.

Although most Americans have a negative view of him personally and question his fitness to be president, Trump has named a new campaign chief, Stephen Bannon, who reportedly believes the GOP nominee should double down on his nationalist, populist, law-and-order message, not temper it.

It’s almost as if Trump has decided that if he’s going to lose in a historic landslide — and every recent national poll suggests he could — he’d prefer to go down swinging as the authentic Trump that he so enjoyed displaying in the primaries rather than an awkward imitation of a mainstream candidate.

Whatever the reasons for this campaign reshuffling, it’s likely to be a fatal misreading of the electorate. Trump’s harsh and divisive rhetoric is what scares voters and accounts for his unprecedented negative ratings in polls. The idea that he can entice a significantly larger swath of voters by offering more of the same is delusional.

Trump’s latest move also raises the specter of doom for down-ticket Republicans whether they’ve backed their party’s presidential nominee or not. A weak candidate at the top usually spells trouble for the party as a whole, although the historical record is complex. When Lyndon Johnson crushed Barry Goldwater in 1964, Democrats boosted their already sizable majorities in both the U.S. House and Senate. By contrast, in 1972 Republicans actually lost two Senate seats despite the drubbing that Richard Nixon inflicted on George McGovern — although they did reduce the Democratic House majority by a dozen seats.

Since Trump openly disdains Republican Party leaders, maybe enough voters will distinguish between him and other GOP candidates to limit the damage to the party in November. Republicans in competitive districts like Colorado’s 6th Congressional District, where Mike Coffman is seeking re-election, can only hope that’s the case.

Those who still harbor the notion that Colorado is a purple swing state — at least for this election — should take a look at the latest Quinnipiac poll, released Wednesday. The most interesting news is not that Hillary Clinton trounces Trump 49 to 39 in a head-to-head contest but that Libertarian and Green candidates attract nearly a quarter of the vote when added to the mix.

Indeed, Trump’s position is so weak that he is in a near tie with Libertarian Gary Johnson among independent voters, while Johnson actually crushes Trump among voters 18 to 34 — a stunning signal of youthful discontent with a major-party nominee.

Once upon a time — three years ago, actually — the GOP establishment set out to repair its image with minorities, women and young voters. But GOP primary voters this year had other ideas. They chose a man whose image among a majority in those groups is utterly toxic.

And now Trump is poised to double down with what got him to this perilous pass? It is the definition of willful blindness.

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